1. Field of the Invention
Embodiments of the invention relate to a liquid crystal display module (LCDM), and more particularly, to an LCDM that includes a top cover and a bottom cover to have an improved mechanical strength.
2. Discussion of the Related Art
As the society has entered in earnest upon an information age, a field of display devices that represent all sorts of electrical signals as visual images has developed rapidly and many kinds of flat panel display devices (FPDs), such as liquid crystal display (LCD) devices, plasma display panels (PDPs), field emission display (FED) devices, electroluminescence display (ELD) devices, and so on, have been introduced. Since they have excellent capabilities of a thin profile, light weight and low power consumption, and so on, they are substituted for the cathode ray tube (CRT) rapidly and came into the spotlight.
Among these devices, LCD devices are widely used for notebook computers, monitors, TV, and so on, because of their high contrast ratio and characteristics adequate to display moving images. Generally, an additional light source is required because the LCD panel is a non-emissive-type display device. Accordingly, a backlight unit is disposed under the LCD panel. The LCD device displays images using light produced by the backlight unit and supplied to the LCD panel. The backlight units includes one of a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL) and a light emitting diode (LED) as a light source.
FIG. 1 is an exploded perspective view of the related art LCDM. Referring to FIG. 1, the LCDM includes a liquid crystal panel 11, a backlight unit 20, a main frame 27, a bottom frame 40 and a top frame 30. The liquid crystal panel 11 includes first and second substrates (not shown) facing each other and a liquid crystal layer therebetween. The liquid crystal panel 11 is connected to gate and data printed circuit boards (PCBs) 17 through a flexible circuit board 15 that provide a scanning signal and an image signal to the liquid crystal panel 11, respectively. The printed circuit board 17 extends along end portions of the bottom frame 40, respectively, as dummy spaces. The backlight unit 20 is disposed at a backside of the liquid crystal panel 11. The liquid crystal display panel 11 and the backlight unit 20 are combined using the main frame 27 that can prevent movement of the liquid crystal panel 11 and the backlight unit 20. The top frame 30 cover edges of the liquid crystal panel 11 and sides of the main frame 27, so the top frame 30 can support and protect of the edges of the liquid crystal panel 11 and sides of the main frame 27. The bottom frame 40 covers back edges of the main frame 27, so the bottom frame 40 is combined with the main frame 27 and the top frame 30 for modulation.
The backlight unit 20 includes a lamp 29, a reflective sheet 25, a light guide plate 23 and a plurality of optical sheets 21. The lamp 29 is disposed at a side of the main frame 27 along a length direction of the main frame 27. The reflective sheet 25 is disposed on the bottom cover 40 and has one of white and silver colors. The light guide plate 23 is disposed on the reflective sheet 25, and the plurality of optical sheets 21 is disposed on the light guide plate 23.
With the above mentioned structure, light emitted from the lamp 29 is incident into the light guide plate 23 and is refracted by the light guide plate 23 into the liquid crystal panel 11. By the light passing through the plurality of optical sheets 21, it has a uniform brightness. The liquid crystal panel 11 displays images using the light. It is required for the LCDM to have an improved mechanical strength.
FIG. 2 is an enlarged perspective view of an “A” portion of a top frame in FIG. 1, and FIG. 3 is an enlarged perspective view of a “B” portion of a bottom frame in FIG. 1. Referring to FIG. 2, the top frame 30 has a top surface 31 and side surfaces 33. The top surface 31 covers edges of the liquid crystal panel 11 (of FIG. 1) and has an opening 31a corresponding to the liquid crystal panel 11 (of FIG. 1). The side surfaces 33 extend from the top surface 31, and a corner of each side surface 33 has a dented portion 36 of a rectangular shape. Two adjacent side surfaces 33 are discontinuous due to the dented portion 36. Namely, each corner includes an opening.
Referring to FIG. 3, the bottom frame 40 has a bottom surface 41 and side surfaces 43. The bottom surface 41 covers the backlight unit 20 (of FIG. 1). The side surfaces 43 extend from the top surface 41, and corner of each side surface 43 has a dented portion 46 of a rectangular shape. Two adjacent side surfaces 43 are discontinuous due to the dented portion 46.
On the other hand, based on requirements of light weight and a thin profile, there are requirements on the top frame 30 and the bottom frame 40 to be thinner. As the top frame 30 and the bottom frame 40 become thinner, a mechanical strength in the corners of the top frame 30 and the bottom frame 40 is degraded due to the discontinuous portions. As a result, the top and bottom frames 30 and 40 may be twisted. The LCDM may be twisted depending on the twisted top and bottom frame 30 and 40. To be resolved these problems, new material having an improved mechanical strength is used for the top and bottom frames 30 and 40 or additional elements are formed. However, it causes problems in a fabricating process to be complicated and a production costs to increase.